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Chromag Bassix Seatpost (rigid)

What the checker says3will not fit

Run variant by variant through the mountain bike builder’s own engine. Every sentence below is the checker’s, unedited. Nothing here says this part fits your bike; it says what it does and does not fit among the parts we hold.

Checked against 6104 verified mountain bike parts in this catalog. 5999 produced no finding of any kind. Each variant produces 3 distinct errors and 0 distinct warnings.

Will not fit

  • Will not fiterror · FrameSeatpost too big: Frame seat tube is 30.9mm but Seatpost is 31.6mm - a bigger post cannot fit a smaller tube. On 58 of the 258 verified frames in this catalog. Applies to all 2 variants.
  • Will not fiterror · FrameSeatpost too small: Frame seat tube is 34.9mm but Seatpost is 31.6mm. A shim or adapter may make other sizes or standards work, but that is a modification, not a fit. On 41 of the 258 verified frames in this catalog. Applies to all 2 variants.
  • Will not fiterror · FrameSeatpost too big: Frame seat tube is 27.2mm but Seatpost is 31.6mm - a bigger post cannot fit a smaller tube. On 6 of the 258 verified frames in this catalog. Applies to all 2 variants.
The checker compares the dimensions listed in what we check, and what we don’t. “No conflicts found” means no conflict among those dimensions — not a guarantee that a build works. Errors mean it won’t fit; warnings mean it works but check; infos are notes.

$66.00 MSRP·240 g

2 verified variants

VariantPrice (MSRP)WeightSourceLast checkedBuild
Bassix$66.00240 gmaker’s page2026-07-24Build with this
Bassix (300mm)$66.00not statedmaker’s page2026-09-07Build with this
What the maker states1 stated
  • 31.6 mm diameter.

Source: each variant links the maker’s own page in the table above. Last checked 2026-07-24 to 2026-09-07.

Checked against

The checker ran this model against every verified part below that it has a slot for, the same way it checks a build in the builder. What follows is the verdict it actually produced for that specific pairing — not a recommendation, and not a guarantee any of these parts fits your own bike.

6 of 1863 counterparts with a page of their own that the checker actually probed this model against, in alphabetical order by brand and model — never by price, popularity or the verdict itself.

Where this sits

Chromag Bassix is the first model on that list.Next: Chromag DolomiteAll Chromag seatpost (rigid)sOpen a variant in the builder to see the ones that apply to your own parts